Water-heater.



UNITED STATES PATENT OFFICE.

GUSTAV A. F. AHLBERG, OF PITTSBURG, PENNSYLVANIA.

, WATER-HEATER.

SPECIFICATION forming part of Letters Patent No. 667,856, dated February 5, 1901. Application filed March 13, 1900. Serial No. 8,529. (No model.)

To all whom it may concern.-

Be it known that I, GUsTAv' A. F. AHLBERG, a subject of the King of Sweden and Norway, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Water-Heaters, of which the following is a specification.

My invention relates to water-heaters, and particularly to devices of this general character in which the water is heated by gas that is automatically turned on by the flow of water caused by opening a faucet at any point of the system and in which the gas is automatically turned off when all the faucets are closed. p

The object of my invention is to provide a simple and efficient valve mechanism for use in connection with water-heaters of the general character above indicated which shall automatically control the flow of water in such manner as to insure a supply of water of substantially uniform temperature. With this end in view I have devised the means shown in the accompanying drawings, in which- Figure 1 is a View, partially in front elevation and partially in section, of a cookingrange provided with a water-heater c0nstructed and arranged in accordance with my invention. Fig. 2 is a sectional view of valve mechanism embodying one form of my invention. showing a modified construction.

Referring now particularly to Figs. 1 and 2 of the drawings, the coil of pipe 1, through which the water flows and in which it is heated during its flow, is shown as mounted in a casing'or compartment 2, attached to or forming an integral part of a range 3, which may be otherwise of ordinary or any desired construction. The gas-burners 4, located beneath the coils 1, are also inclosed within the casing 2 and may have the usual construction and arrangement.

The arrangement of the heater as a part of a cooking-range is intended to be illustrative merely, it being understood that the coil and the casing surrounding the samemay be given any convenient location other than that indicated, if desired.

The gas for the burners 4 is supplied from Fig. 3 is a view similar to Fig. 2, but

the street-main or from a pipe connected thereto through a pipe 5, a valve-casing 6, and a pipe 7. The valve-casing6 is provided with a downwardly-closing valve 8 and with a valve-seat 8 therefor. The valve 8 is mounted upon the upper end of a stem 9, which extends downward through suitable stuffingboxes 10 and 11 and is provided at its lower end with a valve 12, which controls the flow of cold water to the heating-coil 1. spring 13 is located in a suitable casing 14, mounted upon the top of the valve-casing 6, and is interposed between a disk or plate 15, carried by the upper end of the stem 9 and a screw-plug 16, the latter being covered by a cap 17, screwed on the upper end of the easing 14. It will be readily seen that by removing the cap 17 access may be had to the screwplug 16 in order to turn it for the purpose of varying the pressure exerted by the spring 13 upon the plate 15.

The parts thus far described may be supported by any suitable means; but I have shown a bracket 18 for this purpose, this bracket being indicated as an integral part of the frame or casing 19, which contains the water-supply-valve mechanism.

Mounted in the casing 19 at one side is a tube 20, preferably formed of brass orsorne other metal that has a large degree of expansion under the influence of heat. This tube 20 is provided nearits upper end with a port 21, to whichis connected a pipe 22, leading from the outlet end of the coil 1, and with a port 23 near its lower end, to which is connected the service-pipe 23, leading through branch pipes to the various faucets which are to be supplied with hot water from the heating-coil 1.

The cold-water-supply pipe 24 is connected to a port 25, which has two openings into a main chamber 26. One of these openings is controlled by the valve 12 and the other constitutes a by-pass 27, the flow of Water through which is controlled by a valve 28, carried by the lower end of a stem 29, formed of steel or other material having a less degree of expansibility when subjected to heat than the material of which the tube 20 is formed. The upper end of the stem 29 is attached to and supported by a cap 30, that is screwed upon A coiled -will be of the temperature desired.

the upper end of the tube 20. The inlet end of the coil lis connected to a port 31 of the chamber 26 by a pipe 32.

In the construction shown in Fig. 3 the several parts are the same in construction and operation as in the form of device shown in Fig. 2 except as regards features which will be specifically pointed out, and since the corresponding features have been designated by the same reference-numerals the description heretofore given in connection with Fig. 2'

may be read in connection with what is shown in Fig. 3, thus rendering unnecessary a repe tition of such description.

The flow of water through the by-pass 27 in the form shown in Fig. 3 is controlled by a downwardly-opening valve 28, the stem 29 of which is connected at its upper end to a piston 33, that is normally pressed upward by a coiled spring 34 in order to move the valve 28 toward its seat. The tube 20,which constitutes the cylinder for the piston 33 and also the casing for the spring 34, contains above the piston 33 a body of liquid 35 of such character that it expands readily under the influence of heat. This liquid is confined within a comparatively small space in the tube 20 by means of the piston 33 below and a suitable screw-plug 36 above.

Any suitable packing devices in addition to those shown may obviously be employed if found necessary ;or desirable.

The hot water fromthe coil 1 passes through a small chamber 37, which surrounds the portion of the tube 20 occupied by the liquid 35, and it its temperature is higher than that for which the apparatus is adjusted it causes the liquid 35 to expand sufficiently to move the piston 33 downward against the action of the spring 34, and thus move the valve 28 away from its seat to a degree that depends upon the temperature of the Water and the expansibility of the liquid 35.

The operation of my inventionis as follows: When a faucet to which the pipe 23' leads, either directly or indirectly,is opened, the water flows from the chamber 26 through the coil 1 and the connecting pipes and passages,

and thus relieves the upper side of the valve- 12 from pressure. The pressure of the cold water entering through the port 25 will therefore raise the valve 12 and at the same time move the gas-valve 8 away from its seat. It being assumed that a pilot-light is continuously burning adjacent to the main burners 4, as is usual in apparatus of this general character, the gas supplied to the burners 4 will be ignited, and the flame will be sufficient tov heat the water to the desired temperature as it passes through the coil 1.

The material and the dimensions of the tube 20 or of the body of liquid 35, as the case may be, will be so selectedand determined as to insure the maintenance of the valve 23 or the valve 28*, as the case may be,- in such position that the water supplied by the heater If it happens, by reason of an extreme heat applied to the coil or by reason of the relatively high temperature of the water flowing in at the port 25, that the heat of the water flowing from the coil is greater than is needed or desired, the tube 20 or the liquid 35, as the case may be, will expand sufficiently to move the by-pass valve farther away from its seat, and

thus permit more water to flow through the by-pass and into the chamber 26. This flow of'water through the by-pass will tend to equalize the pressure onthe two sides of the valve 12, and it will therefore be depressed sufficiently to either entirely or partially cut oif the supply of gas to the burners 4. As soon as the temperature of the water flowing to the faucets is reduced to the desired degree the by-pass valve will close and the normal flow of water through the port 25 will be resumed.

In case the by-pass valve is so located under normal conditions of working that some water Willfiow through the by-pass if the temperature of the water flowing from the heater falls below what is desired the thermostatic device will move the valve toward its seat, and thus insure an increased flow of gas and a consequent increase in the temperature of the water supplied bythe heater.

The several parts of the apparatus may obviously be so adjusted that the by-pass valve will be either seated or at any desired distance'from its seat during normal operation, according to the conditions under which the apparatus is operated. This construction and arrangement of apparatus obviously permits of such an automatic adjustment of the water and gas valves as will insure a supply of hot water of substantially uniform temperature. This isa condition very much to be desired, for the reason that even though variation in the temperature of the hotwater supplied is not in itself particularly undesirable the excessive consumption of gas necessary to heat the water to a higher temperature thanis needed involves unnecessary exture of the watersupplied by the heater, I

desire it to be understood that other forms may be employed, if desired, and that my invention is not limited to any specific thermostatic means or to any particular form or arrangement of valves and cooperating mechanism.

I claim as my invention- 1. In an automatic water-heater, the combination with a water-supply valve and a gassupply valve operated thereby, of a thermostatic device acted upon by the heated water to effect adjustment of the position of the Water-supply valve.

2. In an automatic water-heater, the combination with a water-supply valve and a gassupply valve operated thereby, of a by-pass around said water-supply valve, a valve for supply valve connected to operate together, of a valve for controlling the pressure exerted upon said supply-valves in opposition to the pressure of the inflowing cold water, and a thermostatic device located in the path of the outfiowing hot water and connected to said controlling-valve.

5. In an automatic Water-heater, the combination with a Water-supply valve and a gassupply valve connected to operate together, of a thermostatic device located in the path of the outflowing body of water and means actuated by said device to regulate the supply of gas and cold water.

Intestimony whereof I have hereunto subscribed my name this 12th day of March, 1900.

GUSTAV A. AHLBERG. 

